objective-c - 当 UISearchBar 激活时调整 UIToolbar 的大小

Question

我有一个包含 5 个项目的 UIToolbar:

1. UIBarButtonItem 带图片
2. UIBarButtonItem 弹性宽度
3. UIBarButtonItem 带有自定义 View (UISearchBar)
4. UIBarButtonItem 弹性宽度
5. UIBarButtonItem 带图片

当我选择 UISearchBar 时，我让它保持正确的大小并激活。但是，我希望左侧和右侧的图像消失，并为 UISearchBar 提供 UIToolbar 的整个宽度。我该怎么做？

这是我的: https://dl.dropbox.com/u/3077127/demo_1.mov

这就是我想要的: https://dl.dropbox.com/u/3077127/demo_2.mov

这是我的代码:

#pragma mark View lifecycle

- (void)viewDidLoad {
[...]

    SearchBar *mySearchBar = [[SearchBar alloc] init];
    mySearchBar.delegate = self;
    [mySearchBar sizeToFit];
    [mySearchBar setAutocapitalizationType:UITextAutocapitalizationTypeNone];
    [mySearchBar setTintColor:[UIHelpers getSlColor]];

    CGRect searchBarFrame = mySearchBar.frame;
    searchBarFrame.size.width = 218;
    [mySearchBar setFrame:searchBarFrame];

    UIView *searchBarContainer = [[UIView alloc] initWithFrame:mySearchBar.frame];
    [searchBarContainer addSubview:mySearchBar];
    [searchBarContainer setTag:99];

    UIBarButtonItem *left = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"location-arrow"] style:UIBarButtonItemStyleBordered target:self action:nil];
    UIBarButtonItem *right = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:@"location-arrow"] style:UIBarButtonItemStyleBordered target:self action:nil];
    UIBarButtonItem *flex = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil];
    UIBarButtonItem *search = [[UIBarButtonItem alloc] initWithCustomView:searchBarContainer];

    NSArray *items = [[NSArray alloc] initWithObjects:left, flex, search, flex, right, nil];

    UIToolbar *toolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, 320, 44)];
    [toolbar setItems:items];
    [toolbar setTintColor:[UIHelpers getSlColor]];

    self.tableView.tableHeaderView = toolbar;
    self.tableView.tableFooterView = [[UIView alloc] initWithFrame:CGRectNull];

[...]

    [super viewDidLoad];
}

#pragma mark -

Answer 1

这是我对发布的类似问题的回答 here

正确动画的关键是指定 UIViewAnimationOptionLayoutSubviews 作为动画的选项。